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#include <bits/stdc++.h>
#include <unordered_set>
using namespace std;

#define st first
#define nd second
#define pb push_back
#define mp make_pair
#define klar(v) memset(v, 0, sizeof(v))
#define bust ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define gcd(a, b) __gcd(a, b);
#define debug(x) cout << #x << " " << x << endl;
#define endl "\n"

typedef vector<int> vi;
typedef vector<pair<int, int> > vpii;
typedef vector<long long> vll;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef long long ll;
const int maxn = 1e6+100;

int main(){
    bust
    int n;
    cin >> n;
    int ones = 0;
    int l = maxn;
    for(int i = 0; i < n; i++){
        int x;
        cin >> x;
        if(x == 1)
            ones++;
        else l = min(l, x);
    }
    if(ones >= l){
        cout << 0 << endl;
        cout << l+1 << endl;
        for(int i = 0; i < l; i++)
            cout << i+1 << " " << l+1 << endl;
        return 0;
    }
    else if(ones > 0)
        cout << 1 << endl;
    else{
        cout << 2 << endl;
    }
    cout << 2 << endl;
    cout << 1 << " " << 2 << endl;
}